Experimental Alzheimer's drug bapineuzumab, from Pfizer (PFE.N) and Johnson & Johnson (JNJ.N), may be safer than originally thought, according to two studies by U.S. researchers released on Wednesday. They said that a brain swelling condition called vasogenic edema, which caused a lot of worry over the drug's safety early on, may decrease over time. "It looks like we can treat people for a number of years safely," Dr. Steven Salloway of Butler Hospital and Brown University in Providence, Rhode Island, told the Alzheimer's Association International Conference in Paris.